Managing Virtual Ports

ABSTRACT

Techniques for managing virtual ports are disclosed herein. Each such virtual port may have different associated features such as, for example, privileges, rights or options. When one or more users are in a capture scene of a gesture based system, the system may associate virtual ports with the users and maintain the virtual ports. Also provided are techniques for disassociating virtual ports with users or swapping virtual ports between two or more users.

RELATED CASES

This application is a continuation of U.S. patent application Ser. No.12/434,584 entitled “Managing Virtual Ports” filed on May 1, 2009, theentire contents are incorporated herein by reference.

This application is related by subject matter to U.S. patent applicationSer. No. 12/434,553 entitled “Binding Users to a Gesture Based Systemand Providing Feedback to the Users” filed on May 1, 2009, the contentsof which are hereby incorporated by reference in their entirety.

BACKGROUND

In a typical computing environment, a user has an input device such as akeyboard, a mouse, a joystick or the like, which may be connected to thecomputing environment by a cable, wire, wireless connection, or someother means of connection. If control of the computing environment wereto be shifted from a connected controller to gesture based control, theuser may no longer have a connected device to inform the computingenvironment of the port with which the user is associated. Further, ifmultiple users are in a capture area for a gesture based environment,the system must determine which user's gestures to ignore, and who topay attention to, or who is associated with which port. Finally, ifmultiple users are simultaneously providing gesture based input to acomputing environment, the system may need to distinguish between themultiple users and determine priority or protocol for them.

User experience in a theoretical gesture based control system maypresent several problems as well. For example, when a computingenvironment has a set input such as a controller or keyboard, a user candetermine that he has a controller connected to a port, that he ispressing keys or buttons and that the system is responding. When controlover the computing environment is shifted to gestures of a user, theuser may require feedback that will let them know that he is beingsensed, that he is bound as a controller to a system, and the like.

Accordingly, systems and methods are needed whereby a computingenvironment may select a principal user for a computing environment.There is also a need to have methods and systems for signing a user ontoor off of a system, allowing handoff or otherwise gaining, losing orshifting control of a computing environment when the control is gesturebased.

SUMMARY

Techniques for managing virtual ports are disclosed herein. Techniquesfor binding users to a gesture based system and providing feedback tothe users are also disclosed herein.

In an embodiment, a number of states are defined that represent theuser's level of interaction with virtual ports the system. These statesmay include, for example, an unbound/undetected state, where no user isdetected in a capture area and the capture device is not bound to auser. The states may also include an unbound/detection state, where auser may be detected in an area, but the system has not yet bound to theuser. The states may also include a bound/detected state, where a useris both detected by a capture device and bound to it, and it may be inthis state that a user may provide gesture based commands to a gesturebased system. The system may also be in a bound/undetected state, wherea user who is bound moves out of the detection area of the capturedevice.

Feedback may be provided to the user to indicate the current state ofthe port and to indicate a change in state. Such feedback may, forexample, take the form of a visual display, which may be a lightswitching on or off, changing colors or flashing. Other appropriatetypes of feedback, such as, for example, audio feedback, may also beemployed.

Another embodiment presents systems and methods for associating userswith virtual ports in a gesture based system. A first user entering intoa computing session makes an entry gesture. When the gesture basedsystem detects this entry gesture, the system may associate the firstuser to a primary virtual port. If a second user enters into a capturearea and makes an entry gesture, the system may associate the seconduser with a secondary virtual port. If a third user enters into acapture area and makes an entry gesture, the system may assign the thirduser with a tertiary port. This pattern of assigning users to respectivevirtual ports may be repeated for any number of additional users. Eachvirtual port may have its own set of respective features including, forexample, privileges, rights or options. For example, the primary portmay, although need not necessarily, have additional features that arenot available to the other ports.

In another embodiment, two or more users may decide to change virtualports. For example, if there are two users, where one has the primaryport and the other has the secondary port, the users may make a gesture,for example, a handshake, after which the computer will swap the virtualports of the two users.

In another embodiment, a first user may make an exit gesture to exitgesture based control of the system. In one aspect of this embodiment,if there are other users associated with virtual ports in the computingenvironment, the system may re-associate the virtual ports upon exit bythe first user.

In another embodiment, an application may have specific gestures whichallow for user entry, exit, handoff, system pause and the like. Specificapplications may also ask for volunteers for individual tasks. In such acircumstance, one or more users may make a volunteering gesture, whichmay cause the system to reassign virtual ports for at least the durationof the specific task.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A, 1B and 1C illustrate an example embodiment of a gesture basedcontrol system with a user playing a game.

FIG. 2 illustrates an example embodiment of a capture device that may beused in a gesture based system.

FIG. 3 illustrates an example embodiment of a computing environment thatmay be used to interpret one or more gestures of a user bound to thegesture based system and associated with the virtual port.

FIG. 4 illustrates another example embodiment of a computing environmentthat may be used to interpret one or more gestures of a user bound tothe gesture based system and associated with the virtual port.

FIG. 5 illustrates an example of a previous control environment for agaming system where controllers, connected with a cable or wirelesslymay be used to control a computing environment.

FIG. 6 illustrates multiple users in a capture area of a gesture basedsystem that may be bound the users, provide feedback to them andassociate them with a virtual port.

FIG. 7 illustrates one example of a user as he may be modeled by agesture based system, where the user is modeled as joints and limbs, andthe motion of these joints and limbs may be used to interpret gesturesfor a gesture based computing environment.

FIG. 8 illustrates a series of gestures that a user may make in agesture based system, such gestures may be used to associate one or moreusers with virtual ports, perform handoffs, exit, pause, select, move orthe like.

FIG. 9 depicts a flow diagram for changing a gesture based system froman unbound to a bound state and providing a user feedback of his state.

FIG. 10 depicts a flow diagram for providing a user feedback to a userabout his state when he is moving out of a capture area.

FIG. 11 depicts a flow diagram for associating virtual ports with users.

FIG. 12 depicts a flow diagram for associating virtual ports with two ormore users based on a volunteer request from a gesture based system.

FIG. 13 depicts a flow diagram for creating a handoff of virtual portsbetween two or more users.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

As will be described herein, a gesture based system may bind toindividuals and associate them with virtual ports, while providingfeedback of the binding states and virtual port associations. Otheraspects of a computing environment may adapt to bind or inform a user,associate him with a virtual port, or maintain a consistent experience.

FIGS. 1A and 1B illustrate an example embodiment of a configuration of agesture based system 10 with a user 18 playing a boxing game. In anexample embodiment, the gesture based system 10 may be used to bind,recognize, analyze, track, associate to a human target, providefeedback, and/or adapt to aspects of the human target such as the user18.

As shown in FIG. 1A, the gesture based system 10 may include a computingenvironment 12. The computing environment 12 may be a computer, a gamingsystem or console, or the like. According to an example embodiment, thecomputing environment 12 may include hardware components and/or softwarecomponents such that the computing environment 12 may be used to executeapplications such as gaming applications, non-gaming applications, orthe like.

As shown in FIG. 1A, the gesture based system 10 may further include acapture device 20. The capture device 20 may be, for example, a detectorthat may be used to monitor one or more users, such as the user 18, suchthat gestures performed by the one or more users may be captured,analyzed, and tracked to perform one or more controls or actions withinan application, as will be described in more detail below.

According to one embodiment, the gesture based system 10 may beconnected to an audiovisual device 16 such as a television, a monitor, ahigh-definition television (HDTV), or the like that may provide feedbackabout virtual ports and binding, game or application visuals and/oraudio to the user 18. For example, the computing environment 12 mayinclude a video adapter such as a graphics card and/or an audio adaptersuch as a sound card that may provide audiovisual signals associatedwith the feedback about virtual ports and binding, game application,non-game application, or the like. The audiovisual device 16 may receivethe audiovisual signals from the computing environment 12 and may thenoutput the game or application visuals and/or audio associated with theaudiovisual signals to the user 18. According to one embodiment, theaudiovisual device 16 may be connected to the computing environment 12via, for example, an S-Video cable, a coaxial cable, an HDMI cable, aDVI cable, a VGA cable, a wireless connection or the like.

As shown in FIGS. 1A and 1B, the gesture based system 10 may be used torecognize, analyze, and/or track a human target such as the user 18. Forexample, the user 18 may be tracked using the capture device 20 suchthat the position, movements and size of user 18 may be interpreted ascontrols that may be used to affect the application being executed bycomputer environment 12. Thus, according to one embodiment, the user 18may move his or her body to control the application.

When no user is a the capture area of the capture device 20, the gesturebased system 10 may provide feedback about this unbound/non-detectionstate of the system 10. When the user 18 enters into the capture area ofthe sensing device 20, the feedback state may change from a state ofunbound/non-detection to a feedback state of unbound/detecting. Thesystem 10 may then bind to the user 18, which may change the feedbackstate from unbound/detecting to bound. After the user 18 is bound to agesture based computing environment 12, he may make a gesture which willturn the rest of the system 10 on. The user 18 may also make a secondgesture which will enter him into association with a virtual port. Thefeedback state may change such that a user 18 knows he is associatedwith the virtual port. The user 18 may then provide a series of gesturesto control the gesture based system 10. For example, if the user 18seeks to open one or more menus or pause one or more processes of thesystem 10, he may make a pause or menu gesture. After finishing with thecomputing session, the user may make an exit gesture, which may causethe gesture based system 10 to disassociate the user 18 with the virtualport. This may cause the feedback state to change from the state ofassociated with a virtual port to the state of bound/detected. The user18 may then move out of the range of the sensors, which may cause thefeedback state to change from bound/detected to non-detection. If asystem 10 unbinds from the user 18, the feedback state may change to anunbound state.

As shown in FIGS. 1A and 1B, in an example embodiment, the applicationexecuting on the computing environment 12 may be a boxing game that theuser 18 may be playing. For example, the computing environment 12 mayuse the audiovisual device 16 to provide a visual representation of aboxing opponent 22 to the user 18. The computing environment 12 may alsouse the audiovisual device 16 to provide a visual representation of auser avatar 24 that the user 18 may control with his or her movements ona screen 14. For example, as shown in FIG. 1B, the user 18 may throw apunch in physical space to cause the user avatar 24 to throw a punch ingame space. Thus, according to an example embodiment, the computerenvironment 12 and the capture device 20 of the gesture based system 10may be used to recognize and analyze the punch of the user 18 inphysical space such that the punch may be interpreted as a game controlof the user avatar 24 in game space.

The user 18 may be associated with a virtual port in computingenvironment 12. Feedback of the state of the virtual port may be givento the user 18 in the form of a sound or display on audiovisual device16, a display such as an LED or light bulb, or a speaker on thecomputing environment 12, or any other means of providing feedback tothe user. The feedback may be used to inform the user 18 when he is in acapture area of the capture device 20, if he is bound to the gesturebased system 10, what virtual port he is associated with, and when hehas control over an avatar such as avatar 24. Gestures by user 18 maychange the state of the system 10, and thus the feedback that the user18 receives from the system 10.

Other movements by the user 18 may also be interpreted as other controlsor actions, such as controls to bob, weave, shuffle, block, jab, orthrow a variety of different power punches. Furthermore, some movementsmay be interpreted as controls that may correspond to actions other thancontrolling the user avatar 24. For example, the user 18 may usemovements to enter, exit, turn system on or off, pause, volunteer,switch virtual ports, save a game, select a level, profile or menu, viewhigh scores, communicate with a friend, etc. Additionally, a full rangeof motion of the user 18 may be available, used, and analyzed in anysuitable manner to interact with an application.

In FIG. 1C, the human target such as the user 18 may have an object suchas racket 21. In such embodiments, the user of an electronic game may beholding the object such that the motions of the user and the object maybe used to adjust and/or control parameters of the game, such as, forexample, hitting an onscreen ball 23. The motion of a user holding aracket 21 may be tracked and utilized for controlling an on-screenracket in an electronic sports game. In another example embodiment, themotion of a user holding an object may be tracked and utilized forcontrolling an on-screen weapon in an electronic combat game. Any otherobject may also be included, such as one or more gloves, balls, bats,clubs, guitars, microphones, sticks, pets, animals, drums and the like.

According to other example embodiments, the gesture based system 10 mayfurther be used to interpret target movements as operating system and/orapplication controls that are outside the realm of games. For example,virtually any controllable aspect of an operating system and/orapplication may be controlled by movements of the target such as theuser 18.

As shown in FIG. 2, according to an example embodiment, the image cameracomponent 25 may include an IR light component 26, a three-dimensional(3-D) camera 27, and an RGB camera 28 that may be used to capture thedepth image of a scene. For example, in time-of-flight analysis, the IRlight component 26 of the capture device 20 may emit an infrared lightonto the scene and may then use sensors (not shown) to detect thebackscattered light from the surface of one or more targets and objectsin the scene using, for example, the 3-D camera 27 and/or the RGB camera28. In some embodiments, pulsed infrared light may be used such that thetime between an outgoing light pulse and a corresponding incoming lightpulse may be measured and used to determine a physical distance from thecapture device 20 to a particular location on the targets or objects inthe scene. Additionally, in other example embodiments, the phase of theoutgoing light wave may be compared to the phase of the incoming lightwave to determine a phase shift. The phase shift may then be used todetermine a physical distance from the capture device to a particularlocation on the targets or objects.

According to another example embodiment, time-of-flight analysis may beused to indirectly determine a physical distance from the capture device20 to a particular location on the targets or objects by analyzing theintensity of the reflected beam of light over time via varioustechniques including, for example, shuttered light pulse imaging.

In another example embodiment, the capture device 20 may use astructured light to capture depth information. In such an analysis,patterned light (i.e., light displayed as a known pattern such as gridpattern or a stripe pattern) may be projected onto the scene via, forexample, the IR light component 26. Upon striking the surface of one ormore targets or objects in the scene, the pattern may become deformed inresponse. Such a deformation of the pattern may be captured by, forexample, the 3-D camera 27 and/or the RGB camera 28 and may then beanalyzed to determine a physical distance from the capture device to aparticular location on the targets or objects.

According to another embodiment, the capture device 20 may include twoor more physically separated cameras that may view a scene fromdifferent angles, to obtain visual stereo data that may be resolved togenerate depth information

The capture device 20 may further include a microphone 30. Themicrophone 30 may include a transducer or sensor that may receive andconvert sound into an electrical signal. According to one embodiment,the microphone 30 may be used to reduce feedback between the capturedevice 20 and the computing environment 12 in the gesture based system10. Additionally, the microphone 30 may be used to receive audio signalsthat may also be provided by the user to control applications such asgame applications, non-game applications, or the like that may beexecuted by the computing environment 12.

The capture device 20 may further include a feedback component 31. Thefeedback component 31 may comprise a light such as an LED or a lightbulb, a speaker or the like. The feedback device may perform at leastone of changing colors, turning on or off, increasing or decreasing inbrightness, and flashing at varying speeds. The feedback component 31may also comprise a speaker which may provide one or more sounds ornoises as a feedback of one or more states. The feedback component mayalso work in combination with computing environment 12 or processor 32to provide one or more forms of feedback to a user by means of any otherelement of the capture device, the gesture based system or the like.

In an example embodiment, the capture device 20 may further include aprocessor 32 that may be in operative communication with the imagecamera component 25. The processor 32 may include a standardizedprocessor, a specialized processor, a microprocessor, or the like thatmay execute instructions that may include instructions for receiving thedepth image, determining whether a suitable target may be included inthe depth image, converting the suitable target into a skeletalrepresentation or model of the target, or any other suitableinstruction.

The capture device 20 may further include a memory component 34 that maystore the instructions that may be executed by the processor 32, imagesor frames of images captured by the 3-D camera or RGB camera, userprofiles or any other suitable information, images, or the like.According to an example embodiment, the memory component 34 may includerandom access memory (RAM), read only memory (ROM), cache, Flash memory,a hard disk, or any other suitable storage component. As shown in FIG.2, in one embodiment, the memory component 34 may be a separatecomponent in communication with the image capture component 25 and theprocessor 32. According to another embodiment, the memory component 34may be integrated into the processor 32 and/or the image capturecomponent 25.

As shown in FIG. 2, the capture device 20 may be in communication withthe computing environment 12 via a communication link 36. Thecommunication link 36 may be a wired connection including, for example,a USB connection, a Firewire connection, an Ethernet cable connection,or the like and/or a wireless connection such as a wireless 802.11b, g,a, or n connection. According to one embodiment, the computingenvironment 12 may provide a clock to the capture device 20 that may beused to determine when to capture, for example, a scene via thecommunication link 36.

Additionally, the capture device 20 may provide the depth informationand images captured by, for example, the 3-D camera 27 and/or the RGBcamera 28, and a skeletal model that may be generated by the capturedevice 20 to the computing environment 12 via the communication link 36.The computing environment 12 may then use the skeletal model, depthinformation, and captured images to, for example, create a virtualscreen, adapt the user interface and control an application such as agame or word processor. For example, as shown, in FIG. 2, the computingenvironment 12 may include a gestures library 190. The gestures library190 may include a collection of gesture filters, each comprisinginformation concerning a gesture that may be performed by the skeletalmodel (as the user moves). The data captured by the cameras 26, 27 anddevice 20 in the form of the skeletal model and movements associatedwith it may be compared to the gesture filters in the gesture library190 to identify when a user (as represented by the skeletal model) hasperformed one or more gestures. Those gestures may be associated withvarious controls of an application. Thus, the computing environment 12may use the gestures library 190 to interpret movements of the skeletalmodel and to control an application based on the movements.

FIG. 3 illustrates an example embodiment of a computing environment thatmay be used to interpret one or more gestures in a target recognition,analysis, and tracking system. The computing environment such as thecomputing environment 12 described above with respect to FIGS. 1A-2 maybe a multimedia console 100, such as a gaming console. As shown in FIG.3, the multimedia console 100 has a central processing unit (CPU) 101having a level 1 cache 102, a level 2 cache 104, and a flash ROM (ReadOnly Memory) 106. The level 1 cache 102 and a level 2 cache 104temporarily store data and hence reduce the number of memory accesscycles, thereby improving processing speed and throughput. The CPU 101may be provided having more than one core, and thus, additional level 1and level 2 caches 102 and 104. The flash ROM 106 may store executablecode that is loaded during an initial phase of a boot process when themultimedia console 100 is powered ON.

A graphics processing unit (GPU) 108 and a video encoder/video codec(coder/decoder) 114 form a video processing pipeline for high speed andhigh resolution graphics processing. Data is carried from the graphicsprocessing unit 108 to the video encoder/video codec 114 via a bus. Thevideo processing pipeline outputs data to an A/V (audio/video) port 140for transmission to a television or other display. A memory controller110 is connected to the GPU 108 to facilitate processor access tovarious types of memory 112, such as, but not limited to, a RAM (RandomAccess Memory).

The multimedia console 100 includes an I/O controller 120, a systemmanagement controller 122, an audio processing unit 123, a networkinterface controller 124, a first USB host controller 126, a second USBcontroller 128 and a front panel I/O subassembly 130 that are preferablyimplemented on a module 118. The USB controllers 126 and 128 serve ashosts for peripheral controllers 142(1)-142(2), a wireless adapter 148,and an external memory device 146 (e.g., flash memory, external CD/DVDROM drive, removable media, etc.). The network interface 124 and/orwireless adapter 148 provide access to a network (e.g., the Internet,home network, etc.) and may be any of a wide variety of various wired orwireless adapter components including an Ethernet card, a modem, aBluetooth module, a cable modem, and the like.

System memory 143 is provided to store application data that is loadedduring the boot process. A media drive 144 is provided and may comprisea DVD/CD drive, hard drive, or other removable media drive, etc. Themedia drive 144 may be internal or external to the multimedia console100. Application data may be accessed via the media drive 144 forexecution, playback, etc. by the multimedia console 100. The media drive144 is connected to the I/O controller 120 via a bus, such as a SerialATA bus or other high speed connection (e.g., IEEE 1394).

The system management controller 122 provides a variety of servicefunctions related to assuring availability of the multimedia console100. The audio processing unit 123 and an audio codec 132 form acorresponding audio processing pipeline with high fidelity and stereoprocessing. Audio data is carried between the audio processing unit 123and the audio codec 132 via a communication link. The audio processingpipeline outputs data to the A/V port 140 for reproduction by anexternal audio player or device having audio capabilities.

The front panel I/O subassembly 130 supports the functionality of thepower button 150 and the eject button 152, as well as any LEDs (lightemitting diodes) or other indicators exposed on the outer surface of themultimedia console 100. A system power supply module 136 provides powerto the components of the multimedia console 100. A fan 138 cools thecircuitry within the multimedia console 100.

The front panel I/O subassembly 130 may include LEDs, a visual displayscreen, light bulbs, a speaker or any other means that may provide audioor visual feedback of the state of control of the multimedia control 100to a user 18. For example, if the system is in a state where no usersare detected by capture device 20, such a state may be reflected onfront panel I/O subassembly 130. If the state of the system changes, forexample, a user becomes bound to the system, the feedback state may beupdated on the front panel I/O subassembly to reflect the change instates.

The CPU 101, GPU 108, memory controller 110, and various othercomponents within the multimedia console 100 are interconnected via oneor more buses, including serial and parallel buses, a memory bus, aperipheral bus, and a processor or local bus using any of a variety ofbus architectures. By way of example, such architectures can include aPeripheral Component Interconnects (PCI) bus, PCI-Express bus, etc.

When the multimedia console 100 is powered ON, application data may beloaded from the system memory 143 into memory 112 and/or caches 102, 104and executed on the CPU 101. The application may present a graphicaluser interface that provides a consistent user experience whennavigating to different media types available on the multimedia console100. In operation, applications and/or other media contained within themedia drive 144 may be launched or played from the media drive 144 toprovide additional functionalities to the multimedia console 100.

The multimedia console 100 may be operated as a standalone system bysimply connecting the system to a television or other display. In thisstandalone mode, the multimedia console 100 allows one or more users tointeract with the system, watch movies, or listen to music. However,with the integration of broadband connectivity made available throughthe network interface 124 or the wireless adapter 148, the multimediaconsole 100 may further be operated as a participant in a larger networkcommunity.

When the multimedia console 100 is powered ON, a set amount of hardwareresources are reserved for system use by the multimedia consoleoperating system. These resources may include a reservation of memory(e.g., 16 MB), CPU and GPU cycles (e.g., 5%), networking bandwidth(e.g., 8 kbs), etc. Because these resources are reserved at system boottime, the reserved resources do not exist from the application's view.

In particular, the memory reservation preferably is large enough tocontain the launch kernel, concurrent system applications and drivers.The CPU reservation is preferably constant such that if the reserved CPUusage is not used by the system applications, an idle thread willconsume any unused cycles.

With regard to the GPU reservation, lightweight messages generated bythe system applications (e.g., popups) are displayed by using a GPUinterrupt to schedule code to render popup into an overlay. The amountof memory required for an overlay depends on the overlay area size andthe overlay preferably scales with screen resolution. Where a full userinterface is used by the concurrent system application, it is preferableto use a resolution independent of application resolution. A scaler maybe used to set this resolution such that the need to change frequencyand cause a TV resynch is eliminated.

After the multimedia console 100 boots and system resources arereserved, concurrent system applications execute to provide systemfunctionalities. The system functionalities are encapsulated in a set ofsystem applications that execute within the reserved system resourcesdescribed above. The operating system kernel identifies threads that aresystem application threads versus gaming application threads. The systemapplications are preferably scheduled to run on the CPU 101 atpredetermined times and intervals in order to provide a consistentsystem resource view to the application. The scheduling is to minimizecache disruption for the gaming application running on the console.

When a concurrent system application requires audio, audio processing isscheduled asynchronously to the gaming application due to timesensitivity. A multimedia console application manager (described below)controls the gaming application audio level (e.g., mute, attenuate) whensystem applications are active.

Input devices (e.g., controllers 142(1) and 142(2)) are shared by gamingapplications and system applications. The input devices are not reservedresources, but are to be switched between system applications and thegaming application such that each will have a focus of the device. Theapplication manager preferably controls the switching of input stream,without knowledge the gaming application's knowledge and a drivermaintains state information regarding focus switches. The cameras 27, 28and capture device 20 may define additional input devices for theconsole 100.

FIG. 4 illustrates another example embodiment of a computing environment220 that may be the computing environment 12 shown in FIGS. 1A-2 used tointerpret one or more gestures in a target recognition, analysis, andtracking system. The computing system environment 220 is only oneexample of a suitable computing environment and is not intended tosuggest any limitation as to the scope of use or functionality of thepresently disclosed subject matter. Neither should the computingenvironment 220 be interpreted as having any dependency or requirementrelating to any one or combination of components illustrated in theexemplary operating environment 220. In some embodiments the variousdepicted computing elements may include circuitry configured toinstantiate specific aspects of the present disclosure. For example, theterm circuitry used in the disclosure can include specialized hardwarecomponents configured to perform function(s) by firmware or switches. Inother examples embodiments the term circuitry can include a generalpurpose processing unit, memory, etc., configured by softwareinstructions that embody logic operable to perform function(s). Inexample embodiments where circuitry includes a combination of hardwareand software, an implementer may write source code embodying logic andthe source code can be compiled into machine readable code that can beprocessed by the general purpose processing unit. Since one skilled inthe art can appreciate that the state of the art has evolved to a pointwhere there is little difference between hardware, software, or acombination of hardware/software, the selection of hardware versussoftware to effectuate specific functions is a design choice left to animplementer. More specifically, one of skill in the art can appreciatethat a software process can be transformed into an equivalent hardwarestructure, and a hardware structure can itself be transformed into anequivalent software process. Thus, the selection of a hardwareimplementation versus a software implementation is one of design choiceand left to the implementer.

In FIG. 4, the computing environment 220 comprises a computer 241, whichtypically includes a variety of computer readable media. Computerreadable media can be any available media that can be accessed bycomputer 241 and includes both volatile and nonvolatile media, removableand non-removable media. The system memory 222 includes computer storagemedia in the form of volatile and/or nonvolatile memory such as readonly memory (ROM) 223 and random access memory (RAM) 260. A basicinput/output system 224 (BIOS), containing the basic routines that helpto transfer information between elements within computer 241, such asduring start-up, is typically stored in ROM 223. RAM 260 typicallycontains data and/or program modules that are immediately accessible toand/or presently being operated on by processing unit 259. By way ofexample, and not limitation, FIG. 4 illustrates operating system 225,application programs 226, other program modules 227, and program data228.

The computer 241 may also include other removable/non-removable,volatile/nonvolatile computer storage media. By way of example only,FIG. 4 illustrates a hard disk drive 238 that reads from or writes tonon-removable, nonvolatile magnetic media, a magnetic disk drive 239that reads from or writes to a removable, nonvolatile magnetic disk 254,and an optical disk drive 240 that reads from or writes to a removable,nonvolatile optical disk 253 such as a CD ROM or other optical media.Other removable/non-removable, volatile/nonvolatile computer storagemedia that can be used in the exemplary operating environment include,but are not limited to, magnetic tape cassettes, flash memory cards,digital versatile disks, digital video tape, solid state RAM, solidstate ROM, and the like. The hard disk drive 238 is typically connectedto the system bus 221 through a non-removable memory interface such asinterface 234, and magnetic disk drive 239 and optical disk drive 240are typically connected to the system bus 221 by a removable memoryinterface, such as interface 235.

The drives and their associated computer storage media discussed aboveand illustrated in FIG. 4, provide storage of computer readableinstructions, data structures, program modules and other data for thecomputer 241. In FIG. 4, for example, hard disk drive 238 is illustratedas storing operating system 258, application programs 257, other programmodules 256, and program data 255. Note that these components can eitherbe the same as or different from operating system 225, applicationprograms 226, other program modules 227, and program data 228. Operatingsystem 258, application programs 257, other program modules 256, andprogram data 255 are given different numbers here to illustrate that, ata minimum, they are different copies. A user may enter commands andinformation into the computer 241 through input devices such as akeyboard 251 and pointing device 252, commonly referred to as a mouse,trackball or touch pad. Other input devices (not shown) may include amicrophone, joystick, game pad, satellite dish, scanner, or the like.These and other input devices are often connected to the processing unit259 through a user input interface 236 that is coupled to the systembus, but may be connected by other interface and bus structures, such asa parallel port, game port or a universal serial bus (USB). The cameras27, 28 and capture device 20 may define additional input devices for theconsole 100. A monitor 242 or other type of display device is alsoconnected to the system bus 221 via an interface, such as a videointerface 232. In addition to the monitor, computers may also includeother peripheral output devices such as speakers 244 and printer 243,which may be connected through a output peripheral interface 233.

The computer 241 may operate in a networked environment using logicalconnections to one or more remote computers, such as a remote computer246. The remote computer 246 may be a personal computer, a server, arouter, a network PC, a peer device or other common network node, andtypically includes many or all of the elements described above relativeto the computer 241, although only a memory storage device 247 has beenillustrated in FIG. 4. The logical connections depicted in FIG. 2include a local area network (LAN) 245 and a wide area network (WAN)249, but may also include other networks. Such networking environmentsare commonplace in offices, enterprise-wide computer networks, intranetsand the Internet.

When used in a LAN networking environment, the computer 241 is connectedto the LAN 245 through a network interface or adapter 237. When used ina WAN networking environment, the computer 241 typically includes amodem 250 or other means for establishing communications over the WAN249, such as the Internet. The modem 250, which may be internal orexternal, may be connected to the system bus 221 via the user inputinterface 236, or other appropriate mechanism. In a networkedenvironment, program modules depicted relative to the computer 241, orportions thereof, may be stored in the remote memory storage device. Byway of example, and not limitation, FIG. 4 illustrates remoteapplication programs 248 as residing on memory device 247. It will beappreciated that the network connections shown are exemplary and othermeans of establishing a communications link between the computers may beused.

FIG. 5 illustrates an example embodiment of a prior art system usingonly connected controls. In such an embodiment, controllers 294, such asa gaming controller, a joystick, a mouse, a keyboard or the like areconnected to a computing environment 12 either with a cable 292 orwirelessly. Pressing particular buttons or keys may cause set signals tobe sent to the computing environment. Further, these controllers aretypically associated with specific physical ports 290. In an example ofa gaming environment, controller 1 may be plugged into a first physicalport, controller 2 may be plugged into a second physical port etc. Thecontroller 1 may have associated therewith primacy of control, orcontrol of certain aspects of the gaming environment that are notavailable to the other controllers. For example, when selecting aspecific level or board in a fighting game, only the first controllermay be able to choose.

The gesture based system such as gesture based system 10 may need toassociate virtual ports with one or more users, and to associate a firstcontroller with a user without using the physical cables and ports ofthe prior art. If there are multiple users, each associated with avirtual port, the users may need feedback to determine with which portsthey are associated. If, after initial association of a user to avirtual port, the port needs to be re-associated with a second user,both users may need some feedback to indicate that the virtual port hasre-associated. When the virtual ports re-associate with different users,additional audio or visual feedback (in addition to the standardfeedback that may be displayed continually) may be provided at or nearthe time of the re-association to further alert the users that there-association has occurred. Other aspects of each users gamingenvironment, such as their characters on the screen, the side of thescreen they may be on in a split-screen game, and other aspects may notchange with the re-association of the virtual port.

FIG. 6 illustrates a capture area 300 as may be captured by capturedevice 20 as described above with regard to FIG. 2. In an embodiment, ifthere are no users in a capture area, such as capture area 300, thefront panel of the computing environment 12, the capture device 20 oraudiovisual display 16 may provide feedback of that first state. Such afirst state may be considered an unbound/no-detection state.

In a second embodiment of FIG. 6, a first user 302 may have steppedpartially into a capture area 300. In FIG. 6, the first user 302, is notfully within the capture area 300 of capture device 20, which may meanthat the gesture based system 10 may not be able to bind to the firstuser 302. In such an event, feedback provided to the first user 302 bycomputing environment 12, or capture device 20 or by audiovisual display16 may depict an unbound/detected state. The gesture based controlsystem 10 may be in the unbound/detected state anytime a user steps intoa capture area, or when a user is only partially in the capture area asis user 302.

In another embodiment, a second user 304 may be in the capture area 300.In such an event, the gesture based control system 10 may have bound thesecond user 304 as a controller of the gesture based control system 10.Feedback may be provided to user 304 in the form of a bound state offeedback by at least one of the capture device 20, audiovisual display16 or computing environment 12.

In another aspect, if a second user such as 304 is bound to the gesturebased control system and steps out of the capture area 300, the systemmay enter a state where the second user 304 is still bound to the system10 but is not currently detected. Such a state may be a bound/undetectedstate. Feedback may be provided by at least one of capture device 20,computing environment 12 or audiovisual device 16 when the second user304 returns to the capture area 300 during the time period when he isstill bound to the gesture based control system. The association of theuser with virtual ports and the like will be maintained while the userhas exited the capture area 300.

If multiple users are in a capture area 300, the gesture based controlsystem 10 may provide feedback about the state of each user in thecapture area. For example, all users may be bound to the gesture basedsystem 10 and associated with virtual ports and be provided a state ofbound/associated feedback specific to each user. The feedback providedmay also include feedback to the first user 302 and the second user 304about which virtual port they may be associated. For example, the firstuser 302 may be associated with the primary virtual port, and feedbackmay be provided to indicate to the first user 302 that he is associatedwith the primary virtual port.

In another aspect of a gesture based control system 10 with a capturearea 300, a user may step too far, too close, or too much to either theleft or the right of the capture device 20. In such a circumstance, thegesture based control system 10 may provide feedback in the form ofeither an ‘out of range’ signal, or specific feedback informing a userthat he may need to move in a particular direction in order for thecapture device 20 to properly capture his image. For example, if asecond user 304 moves too far to the left, then an arrow may pop up onthe screen directing him back to the right. Such directions provided tothe user may also be provided by the capture device 20, or the computingenvironment 12. An audio signal may accompany such visual feedback asdescribed above.

In one embodiment, the different feedback states take the form ofdifferent color light emitters. For example, feedback for an‘unbound/undetected’ state may be black or powered down, feedback for an‘unbound/detected’ state may be yellow, feedback for a ‘bound/detected’state may be green, and feedback for a ‘bound/undetected’ or ‘out ofrange’ state may be blue. This color scheme is merely provided as anexample, and any other color scheme may be used. In another embodiment,the feedback states may involve flashing vs. constantly emitting lights.For example, the feedback for an ‘unbound/undetected’ state may bepowered off, feedback for an ‘unbound/detected’ state may be flashing,and feedback for a bound state may be constantly emitting. In anotherembodiment, there may be audio feedback for shifts between states, orduring a particular state. The feedback provided to a user about hisstate as a controller of computing environment 12 may include anycombination of the above examples and any other appropriate feedback.

The feedback to each user may be associated with an avatar or particularlight or display on the capture device 20, the computing environment 12or the audiovisual display 16. There may be changes in which virtualport a user is associated with during one or more computing sessions.Certain embodiments may provide feedback to users that they haveswitched from one virtual port to another, however, certain aspects ofthe computing environment and the feedback to the users may remain thesame. For example, if a user has a particular light or LED associatedwith his session, the light or LED may still represent him even if heswitches virtual ports. In another example, the avatar associated with auser may remain the same even if the user switches virtual ports. As afurther example, an avatar of a user may be highlighted or otherwiseshow some shift in appearance if the user switches virtual ports. Inanother embodiment, if there is a split screen game or side of a screenthat a user starts a session on, then these elements may not change ifthere is a re-association of virtual ports.

FIG. 7 depicts a model of a human user 510 that may be created using thecapture device 20 and the computing environment 12. This model may beused by one or more aspects of the gesture based system 10 to determinegestures and the like. The model may be comprised of joints 512 andbones 514. Tracking these joints and bones may allow the gesture basedsystem to determine what gestures a user is making. These gestures maybe used to control the gesture based system.

FIG. 8 depicts a series of gestures such as a wave or raised hand 520,making an X with arms 522, or a high five 524. Although not limited inany way by the few gestures that have been depicted, these gestures,along with any others may be commands for the gesture based system 10.In one embodiment, gestures may be universal, meaning that they wouldnot be limited to particular software or hardware applications. Inanother embodiment games or other programs operated on computingenvironment 12 may have program specific gestures. For example, auniversal gesture to handoff a virtual port may be a handshake; however,a game such as a wrestling game may have a program specific gesturewhich performs a handoff of control if the users perform a high-five524.

Universal gestures for binding and associating users to virtual portsmay include a gesture for associating the user making the gesture with avirtual port, a gesture to disassociate with a virtual port, a pausegesture, a menu gesture, a volunteer gesture, a system power on gesture,a system power off gesture, a select gesture, an exit gesture, a handoffgesture and the like.

FIG. 9 depicts a block diagram 600 for binding a user to the gesturebased system and providing feedback to him regarding his state. In oneembodiment, the process for entering a user as a controller involves thesteps of detecting the user, then binding to them and then detecting aspecific command which associates the user with a virtual port. Withoutsome sort of feedback from the system, a user may be unaware of hisstatus in the gesture based system. For example, a user in an‘unbound/detected’ state may be frantically making a gesture to, forexample, turn the system on. The system may be incapable of performingthis function until a user is in a bound state, which may lead tofrustration for the user if he is unaware of his state in the gesturebased system. As another example, if a user who is bound to the gesturebased system and associated with a virtual port moves out of the rangeof detection by the capture device, the system may lose the ability toreceive commands. In such a circumstance, it may be important to providefeedback to the user informing him that he may need to move in order toreturn to the capture area and input gesture based commands to thegesture based system.

At 602, when no user is detected in the capture area, the gesture basedsystem may be in an unbound/non-detection state and may be providingfeedback representing this state. This feedback may be, for example, anoff state of a light emitter, or a silent state from a speaker, or itmay be a light emitter of a certain color or shape or periodicity.

At 604, one or more of the sensors on capture device 20 described abovewith respect to FIGS. 1A-1B may detect a user. In one embodiment, theuser enters into the capture area of one or more of the cameras of thecapture device. In another embodiment, a microphone or the like detectsnoise from a user.

At 606, when a user is detected, the feedback state of the gesturesystem may switch from a feedback state of ‘unbound/non-detection’ to astate of ‘unbound/detection’. This feedback state may be a lightemission of a particular color, a noise, or a flashing light emitter. Inone embodiment, this state is skipped completely, and the only feedbackstates are bound and unbound.

At 608, the gesture based system may bind to the user. Binding may occurwhen the system builds a model such as model 510 described with respectto FIG. 7. In another embodiment, binding may involve looking up one ormore user profiles and comparing the model of the user with the userprofiles. After binding at 608, the system is in a state such that itmay receive and interpret gestures as commands from a user.

At 610, the system may provide feedback to a user informing him that heis in the bound state. As above, this feedback may take the form of anynoise or light emission on any screen, surface or projection from thegesture based system.

FIG. 10 depicts a block diagram 620 for unbinding a user from a gesturebased system. In one embodiment, at 622 a port and user are in a boundstate. The user may merely walk out of a capture area, such as capturearea 300, which is detected at 624. If a user does not return, thefeedback state switches from a state of bound to a state ofunbound/undetected at 628. In one embodiment, there may be a delaybetween the time that a user such as user 18 exits a capture area andwhen the system becomes unbound and provides unbound feedback to theuser. Such a delay may allow a user to exit a capture area during asession, or for a short period of time and to return to the capture areahaving maintained his virtual port and other elements of his computingsession.

FIG. 11 depicts a block diagram 640 for an example embodiment toassociate one or more people to virtual ports of a gesture based system.In a gesture based system, a user typically does not have a controllerwith an established physical port. Instead, the system must assignvirtual ports to one or more users. Further, these virtual ports mayneed to be assigned as either primary or secondary or tertiary or thelike and may have associated with them different features, such as, forexample, privileges, rights or options. These features may change duringthe course of one or more computing sessions.

At 642 a user may be bound to the system as described above. Once a useris bound to a gesture based system, he may be able to provide commandsto the system by making one or more gestures. One such gesture may be anentry gesture. The gesture based system may detect an entry command fromthe first user at 644. The entry command is an optional feature, and theuser need not necessarily provide an entry command in order to beassociated with a port. In some cases, simply entering or being detectedin a capture area may be sufficient to be associated with a port.

At 646, the gesture based system may associate the user to the primaryvirtual port. The primary virtual port may have additional controls overthe gesture based system that other ports associated with a gesturebased system may not have. For example, the user associated with theprimary port may be allowed to make initial selections on menu or titlepages. The user associated with the primary port may also be the firstto make selections for avatars or other elements such as boards or thelike in a gaming environment.

At 648, a second user may enter may be detected in a capture area andbound to a gesture based system. Once the second user is bound to agesture based system, he may be able to provide commands to the systemby making one or more gestures. One such gesture may be an entrygesture. The entry gesture provided by the second user may be the sameas of different from the entry gesture provided by the first user. Theremay be one or more entry gestures, any one of which a user may provideto a gesture based system in order to associate with a virtual port. Theentry command is an optional feature, and the user need not necessarilyprovide an entry command in order to be associated with a port. In somecases, simply entering or being detected in a capture area may besufficient to be associated with a port.

At 652, the second user may be associated with a secondary virtual port.The secondary virtual port may have features that are different thanthose associated with the primary virtual port. In one example, thesecondary virtual port may have associated therewith a cursor; however,the cursor may not be used for making selections on certain menu screensor selection screens or the like. In another example, the secondaryvirtual port may be used for selecting one or more options on certainscreens when the primary virtual port may not have rights to makeselections. For example, the second user may be able to select an avataror the like when the first user may not have any control over the screenor a portion of the screen.

FIG. 12 depicts a block diagram 660 for a gesture based systemrequesting a volunteer and assigning virtual ports based on thevolunteering. At 662, two or more users may be bound to a gesture basedenvironment and may be associated with two or more ports, one of whichis the primary port.

At 664, the gesture based environment may provide the users with arequest for one or more volunteers. In one embodiment, this process maybe used to reassign one or more virtual ports to one or more users. Inanother embodiment, the volunteering may be used in a software orhardware application such as a gaming application where one or moreusers may be assigned specific tasks. The gesture based system mayrequest that a user make a volunteer gesture, move to a specific pointin the capture area, or there may be a universal gesture that a user maymake to act as a volunteer. In another embodiment, the gesture basedenvironment may project a virtual spotlight into the room, and avolunteer may step into this virtual spotlight, which may have an onscreen representation, in order to volunteer.

At 666, the system may detect on or more volunteer gestures from one ormore users. The gesture based system may re-associate the virtual portsat 668 based on the volunteering gestures. In one embodiment, when auser volunteers, the primary port may be associated with them for theduration of the volunteering task. In another embodiment, the primaryport may be associated with a user who volunteers until the session endsor another event that creates a re-association of virtual ports happens.While the virtual ports may be re-associated, other aspects of thesystem may remain the same. For example, avatars, positions, feedbackand the like may not change with the re-association of a virtual port.In another embodiment, at least one of avatars, positions feedback orthe like changes when the virtual ports change associations betweenusers.

FIG. 13 depicts a block diagram 680 of an exemplary method for handingoff or switching virtual ports between two or more users. At 682, one ormore users may be associated with one or more virtual ports in acomputing environment. One of the users may make a handoff gesture whichis detected by the gesture based system at 684. The gesture based systemmay re-associate one or more virtual ports based on the handoff gestureat 686.

As an example, a first user associated with a first virtual port maymake a handoff gesture to a second user that is not currently associatedwith any virtual port. This may cause the first virtual port to beswitched from the first user to the second user. This may also cause thefirst user to be reassigned to another available virtual port.

As another example, a first user associated with a first virtual portmay make a handoff gesture to a second user that is currently associatedwith a second virtual port. This may cause the first virtual port to beswitched from the first user to the second user. This may also cause thesecond virtual port to be switched from the second user to the firstuser.

As another example, such as a tag team wrestling game, two or more usersmay high five in order to hand off a virtual port or control of thegame. In the tag team wrestling example, it may be that each user isassociated with a virtual port, but that only one user at a time may beassociated with the primary port and thus be able to perform certaincommands that are exclusive to the primary port. A high five may signalthat the primary port will switch users, thus allowing the other user toperform gesture based commands that are exclusive to the primary port.As another example, certain handoff gestures may allow sets of users tocontrol certain items or objects simultaneously. For example, prior to ahandoff gesture, only a first user may be able to enter commands tocontrol an avatar in a wrestling ring. However, after a handoff gesture,both the first user and the second user may be able to control theavatar simultaneously.

A gesture based system 12 may have memory 112 or memory 32 or any othermemory in computing environment 12 with reference to FIGS. 2 and 3. Thememory may have stored thereon one or more profiles containinginformation related to one or more users. In one embodiment, theprofiles may contain information which may automatically associate auser with a virtual port. For example, a user may set a profile storedin memory that will automatically associate him with the primary portwhenever he is in a capture area. As another example, a computingenvironment may store information about one or more users that mayprovide a typical or default order for association of virtual ports. Inanother embodiment, the primary user or owner of a gesture based systemmay be associated with the primary port whenever he is in a capturearea. As another example, a gesture based system may store informationabout the inability that one or more users may have in controlling thegesture based system, thus the system may typically associate them witha secondary or tertiary port or the like.

A gesture based system may also use other information to establishassociations with virtual ports. For example, if one or more childrenstep into a capture area with a parent, the gesture based system maydetermine based on the size and other aspects of a user that there is aparent and children. The computing environment may thereafter associateor re-associate the virtual ports such that the parent is associatedwith the primary virtual port. As another example, if one or more usersmay be having difficulty providing gesture based input to the gesturebased system, the system may re-associate the primary port to anotheruser and provide feedback of the change of associated ports.

It should be understood that the configurations and/or approachesdescribed herein are exemplary in nature, and that these specificembodiments or examples are not to be considered limiting. The specificroutines or methods described herein may represent one or more of anynumber of processing strategies. As such, various acts illustrated maybe performed in the sequence illustrated, in other sequences, inparallel, or the like. Likewise, the order of the above-describedprocesses may be changed.

Additionally, the subject matter of the present disclosure includescombinations and subcombinations of the various processes, systems andconfigurations, and other features, functions, acts, and/or propertiesdisclosed herein, as well as equivalents thereof.

1. A method for managing a gesture based computing environment,comprising: receiving a plurality of depth images of a capture area;generating a model of a first user based on at least part of the firstuser being depicted in one of the depth images and based at least inpart on depth values of pixels of one of the depth images; associatingthe first user with a primary virtual port, the primary virtual porthaving associated therewith a feature that a secondary virtual port doesnot have, a user of the computing environment being able to be bound orunbound to the primary virtual port, the user being bound to the primaryvirtual port being indicative of the user being able to provide input tothe computing environment via the primary virtual port; identifying asecond user based on at least part of the second user being depicted inone of the depth images; associating the second user with the secondaryvirtual port in response to identifying the second user; disassociatingthe first user from the primary virtual port in response to determiningthat the first user is no longer sufficiently depicted in a subsequentdepth image based at least in part on depth values of pixels in thesubsequent depth image; and updating an association of the second userfrom the secondary virtual port to the primary virtual port in responseto dissociating the first user from the primary virtual port.
 2. Themethod of claim 1, wherein determining that the first user is no longersufficiently depicted in the subsequent depth image based at least inpart on depth values of pixels in the subsequent depth image comprises:determining that the first user is exiting or has exited the capturearea based at least in part on depth values of pixels in the subsequentdepth image.
 3. The method of claim 1, wherein updating the associationof the second user from the secondary virtual port to the primaryvirtual port comprises: updating the association of the second user fromthe secondary virtual port to the primary virtual port in response todetermining that the second user is sufficiently depicted in thesubsequent depth image based at least in part on depth values of pixelsin the subsequent depth image.
 4. The method of claim 1, whereinupdating the association of the second user from the secondary virtualport to the primary virtual port comprises: transferring a featureassociated with the first user to the second user.
 5. The method ofclaim 1, wherein associating the first user with the primary virtualport comprises: determining that the first user has performed an entrycommand.
 6. The method of claim 1, wherein associating the first userwith the primary virtual port comprises: associating the first user withthe primary virtual port in response to determining that the first userhas issued a volunteer command in response to issuing a prompt to thefirst and second users for a volunteer.
 7. The method of claim 1,further comprising: determining an aspect of the first user or receivinguser profile information for the first user; and wherein associating thefirst user with the primary virtual port is performed based on theaspect of the first user or the user profile information.
 8. A systemfor managing a gesture based computing environment, comprising: aprocessor; and a memory bearing processor-executable instructions that,when executed on the processor, causes the system to at least: receive aplurality of depth images of a capture area; identify a first user basedon at least part of the first user being depicted in one of the depthimages and based at least in part on depth values of pixels of one ofthe depth images; associate the first user with a primary virtual port,the primary virtual port having associated therewith a feature that asecondary virtual port does not have, a user of the computingenvironment being able to be bound or unbound to the primary virtualport, the user being bound to the primary virtual port being indicativeof the user being able to provide input to the computing environment viathe primary virtual port; identify a second user based on at least partof the second user being depicted in one of the depth images; associatethe second user with the secondary virtual port in response toidentifying the second user; disassociate the first user from theprimary virtual port in response to determining that the first user isno longer sufficiently depicted in a subsequent depth image based atleast in part on depth values of pixels of the subsequent depth image;and update an association of the second user from the secondary virtualport to the primary virtual port in response to dissociating the firstuser from the primary virtual port.
 9. The system of claim 8, whereinthe instructions that, when executed on the processor, cause the systemto at least determine that the first user is no longer sufficientlydepicted in the subsequent depth image based at least in part on depthvalues of pixels in the subsequent depth image further cause the systemto at least: determine that the first user is exiting or has exited thecapture area based at least in part on depth values of pixels in thesubsequent depth image.
 10. The system of claim 8, wherein theinstructions that, when executed on the processor, cause the system toat least update the association of the second user from the secondaryvirtual port to the primary virtual port further cause the system to atleast: update the association of the second user from the secondaryvirtual port to the primary virtual port in response to determining thatthe second user is sufficiently depicted in the subsequent depth imagebased at least in part on depth values of pixels in the subsequent depthimage.
 11. The system of claim 8, wherein the instructions that, whenexecuted on the processor, cause the system to at least update theassociation of the second user from the secondary virtual port to theprimary virtual port further cause the system to at least: transfer afeature associated with the first user to the second user.
 12. Thesystem of claim 8, herein the instructions that, when executed on theprocessor, cause the system to at least associate the first user withthe primary virtual port further cause the system to at least: determinethat the first user has performed an entry command.
 13. The system ofclaim 8, wherein the instructions that, when executed on the processor,cause the system to at least associate the first user with the primaryvirtual port further cause the system to at least: associate the firstuser with the primary virtual port in response to determining that thefirst user has issued a volunteer command in response to issuing aprompt to the first and second users for a volunteer.
 14. The system ofclaim 8, wherein the memory further bears instructions that, whenexecuted on the processor, cause the system to at least: determine anaspect of the first user or receiving user profile information for thefirst user; and wherein the instructions that, when executed on theprocessor, cause the system to at least associate the first user withthe primary virtual port is performed based on the aspect of the firstuser or the user profile information.
 15. A computer-readable storagemedium excluding signals bearing computer executable instructions formanaging a gesture based computing environment that, when executed on acomputer, cause the computer to perform operations comprising: receivinga plurality of depth images of a capture area; generating a model of afirst user based on at least part of the first user being depicted inone of the depth images and based at least in part on depth values ofpixels of one of the depth images; associating the first user with aprimary virtual port, the primary virtual port having associatedtherewith a feature that a secondary virtual port does not have, a userof the computing environment being able to be bound or unbound to theprimary virtual port, the user being bound to the primary virtual portbeing indicative of the user being able to provide input to thecomputing environment via the primary virtual port; identifying a seconduser based on at least part of the second user being depicted in one ofthe depth images; associating the second user with the secondary virtualport in response to identifying the second user; disassociating thefirst user from the primary virtual port in response to determining thatthe first user is no longer sufficiently depicted in a subsequent depthimage based at least in part on depth values of pixels in the subsequentdepth image; and updating an association of the second user from thesecondary virtual port to the primary virtual port in response todissociating the first user from the primary virtual port.
 16. Thecomputer-readable storage medium of claim 15, wherein determining thatthe first user is no longer sufficiently depicted in the subsequentdepth image based at least in part on depth values of pixels in thesubsequent depth image comprises: determining that the first user isexiting or has exited the capture area based at least in part on depthvalues of pixels in the subsequent depth image.
 17. Thecomputer-readable storage medium of claim 15, wherein updating theassociation of the second user from the secondary virtual port to theprimary virtual port comprises: updating the association of the seconduser from the secondary virtual port to the primary virtual port inresponse to determining that the second user is sufficiently depicted inthe subsequent depth image based at least in part on depth values ofpixels in the subsequent depth image.
 18. The computer-readable storagemedium of claim 15, wherein updating the association of the second userfrom the secondary virtual port to the primary virtual port comprises:transferring a feature associated with the first user to the seconduser.
 19. The computer-readable storage medium of claim 15, whereinassociating the first user with the primary virtual port comprises:determining that the first user has performed an entry command.
 20. Thecomputer-readable storage medium of claim 15, wherein associating thefirst user with the primary virtual port comprises: associating thefirst user with the primary virtual port in response to determining thatthe first user has issued a volunteer command in response to issuing aprompt to the first and second users for a volunteer.